What is the initial treatment approach for patients with vasculitis?

Initial Treatment Approach for Vasculitis

The initial treatment approach for vasculitis should include high-dose glucocorticoids (1 mg/kg/day, maximum 60 mg/day prednisone-equivalent) in combination with appropriate immunosuppressive agents based on the type and severity of vasculitis. 1, 2

Classification and Assessment

• Vasculitis should be categorized according to vessel size (large, medium, small) and disease severity to guide appropriate management 2
• ANCA-associated vasculitis (AAV) should be classified as localized, early systemic, generalized, severe, or refractory disease 2
• Disease activity should be assessed using validated tools such as Birmingham Vasculitis Activity Score (BVAS) 2
• In suspected ANCA-associated vasculitis with positive MPO or PR3 serology, treatment should not be delayed while waiting for biopsy results, especially in rapidly deteriorating patients 1

Initial Treatment Approach by Vasculitis Type

Large Vessel Vasculitis (Giant Cell Arteritis, Takayasu Arteritis)

• Initiate high-dose glucocorticoid therapy (1 mg/kg/day, maximum 60 mg/day prednisolone) immediately for induction of remission 1
• Maintain high-dose glucocorticoids for one month before gradual tapering 1
• For Giant Cell Arteritis with symptoms, immediate initiation of high-dose glucocorticoids is recommended to reduce recurrent stroke risk 1
• Consider adjunctive immunosuppressive therapy:
  • For Giant Cell Arteritis: methotrexate or tocilizumab as steroid-sparing agents 1
  • For Takayasu Arteritis: all patients should receive non-biological glucocorticoid-sparing agents in combination with glucocorticoids 1

ANCA-Associated Vasculitis (Granulomatosis with Polyangiitis, Microscopic Polyangiitis)

• Combination therapy with glucocorticoids and either rituximab or cyclophosphamide is recommended as initial treatment 1, 2
• For patients with markedly reduced or rapidly declining GFR (serum creatinine >4 mg/dl), cyclophosphamide plus glucocorticoids, or a combination of rituximab and cyclophosphamide should be considered 1
• Factors favoring cyclophosphamide include severe glomerulonephritis (serum creatinine >4 mg/dl) 1
• Factors favoring rituximab include younger patients concerned about fertility, and those with relapsing disease 1, 3

Dosing and Administration

• Glucocorticoids: Initial dose of 1 mg/kg/day (maximum 60 mg/day) for large vessel vasculitis 1
• Cyclophosphamide: Can be administered orally (2 mg/kg/day) or intravenously (based on weight and renal function) 2
• Rituximab: Standard dosing is 375 mg/m² once weekly for 4 weeks 3
• Prophylaxis against Pneumocystis jiroveci pneumonia and osteoporosis should be considered for patients on immunosuppressive therapy 2

Monitoring and Follow-up

• Regular assessment of disease activity using structured clinical examination and validated tools 2
• Monitor for drug toxicity, including acute fall in white cell count, progressive leukopenia, and renal function 2
• ANCA persistence, increase in ANCA levels, or change from negative to positive may predict future relapse and should be considered when making treatment decisions 1

Special Considerations

• Patients with AAV should be treated at centers with experience in AAV management 1
• For severe disease with pulmonary hemorrhage or rapidly progressive glomerulonephritis, more aggressive initial therapy may be required 1, 4
• The combination of rituximab and cyclophosphamide can be considered for severe disease 1

Common Pitfalls to Avoid

• Delaying treatment while waiting for biopsy results in rapidly deteriorating patients 1
• Using alternate-day glucocorticoid therapy, which increases risk of relapse 1
• Inadequate initial immunosuppression in severe disease 1, 4
• Failure to provide prophylaxis against treatment-related complications 2